High Speed Combatant Craft Automated Ride Control

The development of an automated ride control system for high speed combatant craft is critical to reducing the motions that cause injury to crew and damage to craft and equipment. Ancillary benefits include reduced fuel consumption for improved range of operation and the reduction of wake signature. The objective of this research project is to continue the successful development of ride control systems for high speed combatant craft with the goals of improving motion-reducing performance through the use of not-currently-implemented predictive features that rely on data from additional on-board sensors and real time sea condition models, and additional not-currently-implemented system automation to reduce operator task load. BENEFITS: Ride control systems are well-proven in commercial and military applications. The company proposing this work has successfully fielded ride control systems for relatively small, very high speed combatant craft with impressive results. For example, one application reduced the peak motions-induced shock acceleration on a 11m US Navy RHIB by approximately 50% (from over 12 g’s to less than 6 g’s), and the company’s ride control system is currently being fitted to every new UK MOD high speed special operations craft. It is believed that further sea-induced motion reductions, with commensurate reductions of injury-causing acceleration can be achieved by (a) using data from additional on-board sensors such as radar or radio-frequency wave height telemetry and (b) using data from sea condition models that are updated in real-time by the ride control system embedded controller. Neither approach is currently implemented anywhere in the world as a control input to the ride control system, and mathematical models and control algorithms must be developed to achieve the goal of improved performance. The anticipated benefits of a system employing these features is improved system performance with little increase in system price, which is an aspect that is very important for follow-on commercial applications. That is, excluding the one-time cost of developing models and algorithms, taking input from craft radar or radio-frequency wave height telemetry is merely a systems integration issue rather than additional hardware scope of supply requirement because the candidate craft, whether military or commercial, are always fitted with radar units, and current generation ride control systems are always fitted with conventional motion sensors such as accelerometers, rate gyros, and inclinometers. Further, it is believed that current-generation embedded processors with adequate computational power are commercially available to simultaneously update sea condition models in real time and run the ride control system algorithms in real time. Another aspect of the work being proposed is increased automation to reduce operator task load. Most current generation ride control systems require the operator to change system settings in response to prevailing sea conditions. Some current generation ride control systems have adaptive algorithms, which merely use a gain scheduling approach that is crude and ineffective for high speed craft. The company proposing this work has investigated integration of an artificial intelligence engine into the ride control system, but performance models indicate that the “learning time” is too long for high speed craft operating in confused sea conditions. However, taking data from additional on-board sensors, such as radar or radio-frequency wave-height telemetry, would decrease “learning time” and provide better motions-reducing performance without the operator having to manually change system settings. As above, the anticipated benefits of a system employing this feature is improved system performance with little increase in system price, which is an aspect that is very important for follow-on commercial applications. That is, excluding the one-time cost of developing models and algorithms, taking input from craft radar is merely a systems integration issue rather than additional hardware scope of supply requirement.